Place poblanos, tomatillos, jalapenos and onion cut side down on a baking tray and place in a preheated oven at 425.
Allow ingredients to cook until they blister and then remove from oven.
Remove skin from onions and place in food processor.
Place poblanos, tomatillos and jalapenos in an airtight container and seal, and let sit for 5-10 minutes.
Pour juices that released while roasting into the food processor.
Check peppers and tomatillos, you should be able to peel away skins from peppers and tomatillos.
Tip the roasted skin-free ingredients into the food processor.
Pulse until ingredients are mixed, then add avocado, cilantro, lime juice and salt and pulse some more until combined but still chunky.